In the related art, a printer that prints information on a sheet, in particular, a portable printer on which a battery is mounted and which is portable exists. Such a printer is used, for example, when a delivery dealer delivers packages to homes. In addition, for example, the printer is also used when performing inventory management in, for example, a warehouse or the like.
The delivery dealer wears, for example, a printer on a body and delivers packages to homes. In this case, a sheet (for example, a delivery record or an absent communication slip) on which various types of information are printed on a roll sheet accommodated inside the printer is discharged from an opening portion using the printer.
However, when the printer is used outdoors in rainy weather, water droplets may intrude through the opening portion of the printer. When the water droplets intrude into the printer, there is a problem that bad influence (for example, short circuit of an electrical system) is given to devices inside the printer.